GNGTS 2014 - Atti del 33° Convegno Nazionale

large datasets, now easly collected bymodern computer-assisted, multichannel resistivitymeters. Moreover, refined 2D and 3D inversion codes (e.g., Tripp et al. , 1984; Shima, 1990; Park and Van, 1991; Li and Oldenburg, 1992; Sasaki, 1994; Loke and Barker, 1995; Dahlin and Zhou, 2004; Mauriello and Patella, 2009) make of ERT a must for the imaging of volcanic structures down to a few hundred meters depth. A dedicated time lapse ERT system has been developed for the long-term monitoring of the geothermal fluid circulation in the shallow aquifers at Pisciarelli fumarolic field (Campi Flegrei). Six ERT profiles have been realized in the Pisciarelli area by a dipole-dipole configuration with a full array of maximum 42 electrodes. The dipole-dipole electrode array consists of two sets of electrodes, the current (source) and potential (receiver) electrodes. A dipole is a paired electrode set with the electrodes located Fig. 2 – Resistivity sections related to a repeated profile in SW-NE direction carried out at four different times. All the profiles show a complex electrical distribution, presenting, in particular a resistive overburden on the whole length of the section overlaying more conductive anomalies. Moreover, a strong resistivity body (several hundred of Ohm m) appears in the central part of the survey. for all the times, localized at about 10 m depth from the surface. 214 GNGTS 2014 S essione 1.3